A Short Review of the Separation of Iridium and Rhodium from Hydrochloric Acid Solutions by Solvent Extraction



Iridium and rhodium are among the platinum group metals. The properties, production processes, and aqueous chemistry of both metals are reviewed. The separation of Ir(IV) and Rh(III) from hydrochloric acid solution is dependent on the characteristics of the solvent extraction systems. In most of the extraction conditions, Ir(IV) is selectively extracted over Rh(III) by either amines or neutral extractants. Rh(I) can be selectively extracted over Ir(III) by neutral extractants after Rh(III) is reduced in the presence of a reducing agent. The separation of these two metals using cationic extractants has also been reported. Although selective extraction of one metal over the other is possible, more efficient solvent extraction systems need to be developed.


Separation Solvent extraction Iridium Rhodium Aqueous chemistry 



This work was supported by the Global Excellent Technology Innovation of the Korea Institute of Energy Technology Evaluation and Planning (KETEP), and granted financial resource from the Ministry of Trade, Industry & Energy, Republic of Korea (No. 20165010100810). We also thank Murdoch University for collaboration opportunities.


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Authors and Affiliations

  1. 1.Department of Advanced Materials Science & Engineering, Institute of Rare MetalMokpo National UniversityMokpoKorea
  2. 2.Chemical & Metallurgical Engineering & Chemistry, School of Engineering and Information TechnologyMurdoch UniversityMurdoch, PerthAustralia

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